30.4.3.2 The host_summary_by_file_io and x$host_summary_by_file_io Views

These views summarize file I/O, grouped by host. By default, rows are sorted by descending total file I/O latency.

The host_summary_by_file_io and x$host_summary_by_file_io views have these columns:

• host

  The host from which the client connected. Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background.

• ios

  The total number of file I/O events for the host.

• io_latency

  The total wait time of timed file I/O events for the host.